25. Al-Furqan (The Criterion, The Standard)

Surah: 25   Aya: 32

32. Waqala allatheena kafaroo lawla nuzzila AAalayhi alqur-anu jumlatan wahidatan kathalika linuthabbita bihi fu-adaka warattalnahu tarteelan
  

  Translation

32. And those who disbelieve say: "Why is not the Qur'ân revealed to him all at once?" Thus (it is sent down in parts), that We may strengthen your heart thereby. And We have revealed it to you gradually, in stages. (It was revealed to the Prophet SAW in 23 years.).